Drone technology for deep-sea exploration

June 13, 2018 Karlsruhe researchers want to penetrate unexplored underwater worlds with a drone

The German participant, the ARGGONAUTS from the Fraunhofer Institute for Optronics, System Technology and Image Evaluation IOSB in Karlsruhe reached the final of the seven-million-dollar research competition Shell Ocean Discovery XPRIZE as the only German based team. It is about the exploration of the deep sea by unmanned, automatically operating systems.

32 teams from around the world competed in 2016 to meet the challenge of the Shell Ocean Discovery XPRIZE. Meanwhile, the finalists have made it to the final. "We are thrilled to be among the best nine participants and are now working with a fresh impetus towards the final," says team leader Dr. Ing. Gunnar Brink from Fraunhofer IOSB.

Winning team receives seven million dollar prize money

In the autumn of 2018, the finals will take place and there will be nine finalists in a field trial in direct competition against each other. The task: All drones must survey at least 250 square kilometres of unexplored seabed at 4,000 meters depth within 24 hours. The aim is to provide high-resolution photos of interesting archaeological, biological or geological features. The winning team will win seven million dollars in prize money.

The study of the deep sea should also be affordable for small businesses

So far, it has been necessary for large and expensive expedition ships to explore the deep sea. The approximately 25-strong ARGGONAUTS team pursues the approach of making deepwater exploration affordable on a larger scale for smaller, specialized companies in a few years' time. "In the XPRIZE competition, we are developing a new, lightweight technology. It's designed to cut costs many times over, making mapping and exploring that habitat affordable," says Brink. And this is how it works: "Unmanned, light carrier boats bring small, also unmanned submarines to the site. These dive drones swarm out fully automatically, measuring the seabed and taking pictures of interesting objects and living things," explains Brink.

The ARGGONAUTS rely on self-developed diving drones of around 2.50 meters in length, the "Great Divers". The electrically powered submarines are brought to the scene by an inflatable catamaran, the "Water Strider". Several of these combined over- and underwater systems work together, the so-called swarm.

"Per sonar, the 'Great Diver' probes the seabed. At least one of the submarines also has a powerful LED flash unit and four special cameras on board," says Brink. In order to retrieve the dive drones after fulfilling a mission and bringing them back safely, a special recovery procedure has been developed and patented. The "Water Strider" pulls a safety rope behind it and drives in an ever-narrowing spiral around the "Great Diver" until he has safely hooked the diving drone and can haul it ashore.